Nitrogen → 4,4-difluoro-2-[5-(4-trimethylsilanylethynyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester

HRID 79673Notes

Reaction equation

HRID 79673 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:12][C:11]([F:14])([F:13])[CH2:10][CH:9]1[C:15]1[NH:16][C:17]([C:20]2[CH:25]=[CH:24][C:23](Br)=[CH:22][CH:21]=2)=[CH:18][N:19]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[Si:27]([C:31]#[CH:32])([CH3:30])([CH3:29])[CH3:28].C(N(CC)CC)C.N#N>CN(C=O)C.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.[Cu]I>[C:1]([O:5][C:6]([N:8]1[CH2:12][C:11]([F:14])([F:13])[CH2:10][CH:9]1[C:15]1[NH:16][C:17]([C:20]2[CH:25]=[CH:24][C:23]([C:32]#[C:31][Si:27]([CH3:30])([CH3:29])[CH3:28])=[CH:22][CH:21]=2)=[CH:18][N:19]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

8

Conditions

Temperature
80 °C

Procedure

A solution of 2-[5-(4-bromo-phenyl)-1H-imidazol-2-yl]-4,4-difluoro-pyrrolidine-1-carboxylic acid tert-butyl ester (700 mg, 1.56 mmol), TMS-acetylene (1.11 mL, 7.79 mmol) and triethylamine (1.1 mL, 7.8 mmol) in DMF (8 mL) was degassed with N2 gas for 20 minutes. To the degassed solution was added Pd(PPh3)4 (180 mg, 0.16 mmol) and CuI (14.8 mg, 0.078 mmol). The pressure flask was sealed then heated at 80° C. overnight. After cooling to room temperature, the reaction was concentrated then diluted with EtOAc and washed with water. The aqueous phase was back-extracted two times then the organic phases were combined and dried over Na2SO4. After concentration, the crude material was purified by silica gel chromatography (10-50% EtOAc-hexanes gradient) to afford 4,4-difluoro-2-[5-(4-trimethylsilanylethynyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (547 g, 1.23 mmol, 79% yield). LCMS-ESI+: calc'd for C23H30F2N3O2Si: 446.2 (M+H+). Found: 445.8 (M+H+).

Workup

  1. customThe pressure flask was sealed
  2. temperatureAfter cooling to room temperature
  3. concentrationthe reaction was concentrated
  4. additionthen diluted with EtOAc
  5. washwashed with water
  6. extractionThe aqueous phase was back-extracted two times
  7. dry with materialdried over Na2SO4
  8. concentrationAfter concentration
  9. customthe crude material was purified by silica gel chromatography (10-50% EtOAc-hexanes gradient)

Sources & evidence

ORD record
ord-94a7c8d92ee84672b4681ddc0d983289
Source dataset
uspto-grants-2014_09
Patent number
US08841278B2

Reaction notes

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